There are still other examples of PRO acting to improve cancer cell sensitivity to drug treatment enhancing the effect of rapamycin on human prostate cancer PC3 cells [49], reverting resistance to trastuzumab in HER2 breast cancer [32], inhibiting the stress-related reduction of sunitinib activity in colorectal cancer in an in vivo model [142] and sensitising thyroid cancer cells to the targeted BRAF-V600E inhibitor vemurafenib [72]. This evidence concerns the gene ERBB2 and breast cancer.